July 21, 2003 Earthquake: Yunnan Province, China

Name: July 21, 2003 Earthquake: Yunnan Province, China
Start: 2003-07-21
Location: Yunnan Province, China

July 21, 2003 · M5.9 · 16 deaths · $75 million · 264,878 houses destroyed

A magnitude 5.9 earthquake struck Yunnan Province, China on July 21, 2003 at 15:16:31 UTC, 10 km below the surface. It killed 16 people.

Map

Where it struck, with the other significant earthquakes within 200 km. Circles are sized and colored by magnitude; select one for its page.

The earthquake

Date: July 21, 2003
Time: 15:16:31 UTC
Place: Yunnan Province, China
Magnitude: 5.9 (Mw)
Magnitude scales: Mw 5.9 · Ms 6 · mb 5.4
Focal depth: 10 km (6 mi)
Tsunami: None recorded
Epicenter: 25.975° N, 101.290° E
Country: China
Region: East Asia
USGS record: The USGS’s page for this earthquake

Mw: moment magnitude, based on the slip on the fault and the area that slipped. Ms: surface-wave magnitude. mb: body-wave (P-wave) magnitude. NCEI’s headline magnitude is the best of these for the earthquake.

The toll

Deaths: 16
Injuries: 584
Damage: $75 million
Houses destroyed: 264,878
Houses damaged: 264,878

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

What happened

The USGS’s account of the effects of this earthquake.

At least 16 people killed, 584 injured, 264,878 buildings destroyed, 1,186,000 houses damaged and 1,508 livestock killed in Yunnan. A power station was damaged and landslides blocked roads in the province. Damage estimated at 75 million U.S. dollars.

From the USGS event page for usp000c30u. U.S. Geological Survey text and figures are in the public domain.

Tectonic setting

Why earthquakes happen here, from the USGS tectonic summary.

The July 21 earthquake occurred as the result of strike-slip faulting. Southwestern China is traversed by several major, seismically active, strike-slip faults, and many destructive earthquakes have occurred on lesser strike-slip faults. The epicenter of the July 21 earthquake is about 100 km north-northeast of the large Red River fault and about 100 km west of the large Anninghe fault. The causative fault of the July 21 earthquake has not yet been identified.

In a broad sense, strike-slip faults and earthquakes in southwestern China result from the eastward motion of the Earth's crust that is driven by the collision of the Indian and Eurasian continental plates beneath the Himalaya Mountains and the Tibetan Plateau farther to the west.

From the USGS event page for usp000c30u. U.S. Geological Survey text and figures are in the public domain.

Magnitude estimates

The magnitudes the USGS catalog lists for this earthquake, by scale and by who computed them. NCEI’s own scales are in the table above.

Mag.	Scale	Computed by	Notes
6.0	Mwb, body-wave moment	USGS National Earthquake Information Center	Preferred · Reviewed
5.9	Mw, moment	ISC-GEM global catalog	Final · ±0.1
5.9	Mwc, centroid moment	Global CMT project	Preliminary

What the record says

NCEI’s account, from the sources it cites.

At least 16 people killed, 584 injured, 264,878 buildings

destroyed, 1,186,000 houses damaged and 1,508 livestock killed in Yunnan. A power station was damaged and landslides blocked roads in the province. Damage estimated at 75 million U.S. dollars. (reference #1053)

Sources NCEI cites

The publications NCEI lists for this record. The numbers match the “reference #” notes in its account above.

#1053 National Earthquake Information Center (NEIC) (1971 to 2013). Preliminary Determination of Epicenters (PDE), a weekly and monthly publication, National Earthquake Information Center, U.S. Geological Survey, Golden, Colorado, 1971 to 2013.

Other significant earthquakes nearby

Within 200 km, the deadliest first.

Significant earthquakes of 2003 The 2000s Every quake the USGS located in 2003 Recent earthquakes near here This day in weather history

Sources

Significant earthquakes from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-10-01. NCEI earthquake 5707. The written accounts and the magnitude estimates are from the USGS earthquake catalog, event usp000c30u, matched to this record by time, place and magnitude.